Laars NEOTHERM NTH User manual

Installation and Operation Instructions Document 1218F
H2335500F
WARNING
If the information in this manual is not
followed exactly, a fire or explosion may
result causing property damage, personal
injury or loss of life.
Do not store or use gasoline or other
flammable vapors and liquids in the vicinity
of this or any other appliance.
WHAT TO DO IF YOU SMELL GAS
• Do not try to light any appliance.
• Do not touch any electrical switch; do not
use any phone in your building.
• Immediately call your gas supplier from a
nearby phone. Follow the gas supplier's
instructions.
• If you cannot reach your gas supplier, call
the fire department.
Installation and service must be performed by
a qualified installer, service agency, or gas
supplier.
FOR YOUR SAFETY: This product must be installed and serviced by a professional service technician,
qualified in hot water boiler and heater installation and maintenance. Improper installation and/or operation
could create carbon monoxide gas in flue gases which could cause serious injury, property damage, or
death. Improper installation and/or operation will void the warranty.
AVERTISSEMENT
Assurez-vous de bien suivres les instructions
données dans cette notice pour réduire au
minimum le risque d’incendie ou d’explosion ou
pour éviter tout dommage matériel, toute
blessure ou la mort.
Ne pas entreposer ni utiliser d’essence ni
d’autres vapeurs ou liquides inflammables dans
le voisinage de cet appareil ou de tout autre
appareil.
QUE FAIRE SI VOUS SENTEZ UNE ODEUR DE GAZ:
• Ne pas tenter d’allumer d’appareils.
• Ne touchez à aucun interrupteur. Ne pas vous
servir des téléphones dansle bâtiment où vous
vous trouvez.
• Appelez immédiatement votre fournisseur de
gaz depuis un voisin. Suivez les instructions
du fournisseur.
• Si vous ne pouvez rejoindre le fournisseur de
gaz, appelez le sservice des incendies.
L’installation et l’entretien doivent être assurés par
un installateur ou un service d’entretien qualifié ou
par le fournisseur de gaz.
Installation and Operation
Instructions for
NeoTherm®
Modulating Boiler
Model NTH
Sizes 080–850 MBTU/h
Water Heater
Model NTV
Sizes 150–850 MBTU/h

LAARS Heating Systems
Page 2
TABLE OF CONTENTS
SECTION 1.
General Information
1.1 Introduction...................................................... 4
1.2 Model Identification ......................................... 4
1.3 Appliance Overview......................................... 4
1.4 Warranty.......................................................... 9
1.5 Unpacking ....................................................... 9
1.6 Dimensions...................................................... 9
SECTION 2.
Locating the Appliance
2.1 Locating the Appliance .................................. 11
2.2 Locating Appliance for Correct Vent Distance
from Outside Wall or Roof Termination ......... 11
Section 3.
Venting and Combustion Air
3.1 Combustion Air.............................................. 12
3.1.1 Combustion Air From Room.......................... 12
3.1.2 Ducted Combustion Air ................................. 12
3.2 Venting .......................................................... 13
3.2.1 Venting Requirements Unique to Canada..... 14
3.3 Locating Vent & Combustion Air Terminals... 14
3.3.1 Side Wall Vent Terminal................................ 14
3.3.2 Side Wall Combustion Air Terminal............... 15
3.3.3 Vertical Vent Terminal ................................... 15
3.3.4 Vertical Combustion Air Terminal .................. 15
3.3.5 Installations in the Commonwealth of
Massachusetts .............................................. 15
3.4 Common Vent Test ....................................... 17
Section 4.
Gas Supply and Piping
4.1 Gas Supply and Piping.................................. 18
Section 5.
Pump Requirements
5.1 NeoTherm Boiler Flow and
Head Requirements ...................................... 19
5.2 NeoTherm Water Heater
Flow and Head Requirements....................... 19
Section 6A.
Water Connections - NTH Boiler
6A.1 NTH System Piping: Hot Supply Connections . 20
6A.2 NTH Cold Water Make-Up ............................ 20
6A.3 Freeze Protection .......................................... 21
6A.4 NTH Suggested Piping Schematics .............. 21
6A.5 Recognized Chemicals.................................. 21
Section 6B.
Water Connections - NTV Water Heater
6B.1 NTV Water Quality ........................................ 29
6B.2 Piping Requirements ..................................... 29
6B.3 Cold Water Make-Up..................................... 30
6B.4 Freeze Protection .......................................... 30
6B.5 NTV Suggested Piping Schematics............... 30
6B.6 NTV Suggested Pumps................................. 30
Section 7.
Electrical Connections
7.1 Main Power ................................................... 32
7.2 Pump Connections ........................................ 33
7.3 24 Vac Transformer with Integral
Circuit Breaker............................................... 33
7.4 Hydronic Call for Heat ................................... 33
7.5 Outdoor Air Temperature Sensor .................. 33
7.6 Domestic Hot Water Connection ................... 33
7.7 System Sensor
(lead lag/cascading operation only)............... 33
7.8 External Control Connections........................ 33
7.9 Optional Field Connections ........................... 33
7.10 Lead lag/ Cascading Wiring Connections ..... 33
7.11 Wiring Diagrams............................................ 35
Section 8.
NeoTherm Control Setup and Operation
8.1 Display Navigation......................................... 37
8.2 Ignition Control - Sequence of Events ........... 37
8.3 Modulation Control ........................................ 38
8.4 Pump Control ................................................ 38
8.5 Anti-Short Cycle (ASC).................................. 38
8.5 High Limit ...................................................... 38
8.7 Outlet Water Temperature............................. 38
8.8 Inlet Water Temperature ............................... 38
8.9 Heat Exchanger Temperature Rise............... 38
8.10 Stack Temperature........................................ 38
8.11 Domestic Hot Water Temperature................. 38
8.12 Lead Lag/Cascading ..................................... 38
8.12.1 Lead Lag Setpoint ......................................... 39
8.12.2 Lead Lag Master/Slave Selection.................. 39
8.12.3 Lead Lag Address ......................................... 39
8.12.4 Lead Lag Hysteresis...................................... 39
8.12.5 Lead Lag Base Load Setting ......................... 39
8.13 Boiler Pump Interrupt .................................... 39

NeoTherm Boilers and Water Heaters Page 3
SECTION 9.
Modes of Operation
9.1 Hydronic Heating Demand ............................ 40
9.2 Hydronic Heating with Outdoor Reset ........... 40
9.3 Hydronic Heating with Domestic Hot
Water (DHW) Priority..................................... 40
9.4 Hydronic Heating Using External
Modulation Control ........................................ 40
9.5 Hydronic Heating Using Local Lead-Lag/
Cascading Feature........................................ 41
9.6 Hydronic Heating Using Local Lead-Lag/
Cascading Feature with Indirect Hot Water... 41
9.7 Warm Weather Shutdown ............................. 41
9.8 Domestic Hot Water Demand (NTV only)...... 41
9.9 Domestic Hot Water Heating Using
External Modulation Control .......................... 42
9.10 Domestic Hot Water Heating Using Local
Lead-Lag/Cascading Feature........................ 42
Section 10.
Operating Instructions
10.1 Filling the Boiler System................................ 43
10.2 Operating the Burner and Set Up .................. 43
10.2.1 Burner Operation........................................... 43
10.2.2 Boiler Setup and Adjustment......................... 44
10.3 Shutting Down NeoTherm ............................. 44
10.4 To Restart NeoTherm.................................... 44
SECTION 11.
Maintenance
11.1 System Maintenance..................................... 46
11.2 Appliance Maintenance and Component
Description .................................................... 46
11.2.1 Burner............................................................ 46
11.2.2 Modulating Gas Valve / Venturi ..................... 46
11.2.3 Appliance Control .......................................... 46
11.2.4 Ignitor Assembly............................................ 47
11.2.5 Flame Sensor ................................................ 47
11.2.6 Transformer with Integral Circuit Breaker...... 48
11.2.7 Blower ........................................................... 48
11.2.8 Heat Exchanger Coils.................................... 48
11.2.9 Gas Pressure Switches (optional) ................. 49
11.2.10 Gas Conversion............................................. 49
Section 12.
Trouble Shooting
12.1 Sequence of Operation ................................. 49
12.2 Short Cycling ................................................. 49
12.3 Error Codes ................................................... 49
Section 13.
Replacement Parts
13.1 General Information....................................... 52
13.2 Parts List ....................................................... 52

LAARS Heating Systems
Page 4
SECTION 1.
General Information
WARNING
NeoTherm units must be installed in accordance with
the procedures detailed in this manual, or the LAARS
Heating Systems warranty will be voided. The
installation must conform to the requirements of the
local jurisdiction having authority, and, in the United
States, to the latest edition of the National Fuel Gas
Code, ANSI Z223.1/NFPA54. In Canada, the
installation must conform to the latest edition of CSA
B149.1 Natural Gas and Propane Gas Installation
Code, and/or local codes. Where required by the
authority having jurisdiction, the installation of
NeoTherm boilers must conform to the Standard for
Controls and Safety Devices for Automatically Fired
Boilers, ANSI/ASME CSD-1. Any modifications to the
boiler, its gas controls, or wiring may void the
warranty. If field conditions require modifications,
consult the factory representative before initiating
such modifications.
1.1 Introduction
This manual provides information necessary for
the installation, operation, and maintenance of LAARS
Heating Systems NeoTherm appliances. Read it
carefully before installation.
All application and installation procedures should
be reviewed completely before proceeding with the
installation. Consult the LAARS Heating Systems
factory, or local factory representative, with any
problems or questions regarding this equipment.
Experience has shown that most operating problems are
caused by improper installation.
NeoTherm is protected against over pressurization.
A pressure relief valve is included with each NeoTherm.
Some NeoTherms may require that the PRV be installed
prior to filling the system. Refer to Figures 1-7 for PRV
locations.
IMPORTANT: The inlet gas pressure to the appliance
must not exceed 13" W.C. (3.2kPa).
All installations must be made in accordance with
1) American National Standard Z223.1/NFPA54-Latest
Edition “National Fuel Gas Code” or 2) CSA B149.1
“Natural Gas and Propane Installation Code” and with
the requirement of the local utility or other authorities
having jurisdiction. Such applicable requirements take
precedence over the general instructions contained herein.
All electrical wiring is to be done in accordance
with the local codes, or in the absence of local codes,
with: 1) The National Electrical Code ANSI/NFPA No.
70-latest Edition, or 2) CSA STD. C22.1 “Canadian
Electrical Code - Part 1”. This appliance must be
electrically grounded in accordance with these codes.
1.2 Model Identification
Consult the rating plate on the unit. The following
information describes the model number structure.
(1-2) Model Series Designation
N T = NeoTherm
(3) Usage
H = Hydronic
V = Volume Water
(4-6) Size
0 8 0 = 80,000 BTU/hr input
1 0 5 = 105,000 BTU/hr input
1 5 0 = 150,000 BTU/hr input
1 9 9 = 199,000 BTU/hr input
2 1 0 = 210,000 BTU/hr input
2 8 5 = 285,000 BTU/hr input
3 9 9 = 399,000 BTU/hr input
5 0 0 = 500,000 BTU/hr input
6 0 0 = 600,000 BTU/hr input
7 5 0 = 750,000 BTU/hr input
8 5 0 = 850,000 BTU/hr input
(7) Fuel
N = Natural Gas
P = LP Gas
(8) Options Code
X = Standard Unit
J = CSD-1, FM, GAP, IL Code (size 500-850 only)
(9) Pump Options
N = Pump included (80-500 only)
X = No pump (configuration available for all sizes)
(10) Revision
2 = Second version
1.3 Appliance Overview
See Figures 1 through 7.
Model Nomenclature
12 3 456 7 8 9 10
NT H 2
SERIES
N T USAGE
H - HYDRONIC
V - VOLUME
WATER
SIZE
MBTU/h
0 8 0
1 0 5
1 5 0
1 9 9
2 1 0
2 8 5
3 9 9
5 0 0
6 0 0
7 5 0
8 5 0
FUEL
N - NATURAL
P - PROPANE
OPTIONS CODE
X - STANDARD
J - CSD-1,
FM, GAP,
IL (500-850 only)
PUMP OPTIONS
N - PUMP INCL.
(80-500 only)
X - NO PUMP
REVISION
2 - SECOND

NeoTherm Boilers and Water Heaters Page 5
Figure 1. Location of Components, Sizes 80–105.
Figure 2. Location of Components, Sizes 150-210.